JPH02239225A - Method and device for injecting liquid crystal to liquid crystal cell - Google Patents

Abstract

PURPOSE:To improve the productivity of an element by reducing the pressure of an atmosphere, maintaining the reduced pressure, and immersing only the part near the injection holes of liquid crystal cells into the liquid crystal sucked up from a liquid level by the capillarity in the slits of a cell inserter, and thereby injecting the liquid crystal therein. CONSTITUTION:The pressure in the atmosphere around the liquid crystal cell is reduced from the atm. pressure to a prescribed pressure and the parts of the liquid crystal cells near the injection holes are inserted into the upper part of the slits 16 formed in the cell inserter 15 in the atmosphere of the prescribed atmosphere. The cell inserter 15 is so fixed to a liquid crystal container 14 that the lower part of the slits 16 is dipped in the liquid crystal L. The liquid crystal L dipping the lower part of the respective slits 16 is sucked up by as much as the height H corresponding to the groove width W of the slits 16 by the capillarity. The atmosphere around the liquid crystal cells is restored to the atm. pressure from the prescribed pressure and the liquid crystal is injected into the liquid crystal cells through the injection holes immersed in the liquid crystal. The simultaneous and easy injection of the liquid crystal into the many liquid crystal cell is executed in this way and the productivity of the liquid crystal display element is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method and apparatus for injecting liquid crystal into a liquid crystal cell constituting a liquid crystal display element.

(Prior art) In recent years, demand for liquid crystal display elements has been increasing in various fields because they are thin, lightweight, and consume low power. There is a strong demand for diversification. For this reason, various improvements have been made to methods and devices for injecting liquid crystal into liquid crystal cells, which greatly affect the reliability and manufacturing cost of liquid crystal display elements.

As a conventional method and apparatus for injecting liquid crystal into this type of liquid crystal cell, there is a method employing an immersion injection method as shown in FIGS. 10 and 11, for example. In FIG. 1O, 1 is a liquid crystal cell, and 2 is a liquid crystal container containing a liquid crystal 3. The liquid crystal cell 1 and the liquid crystal container 2 are placed in a vacuum chamber (not shown). Then, when the atmospheric pressure in the vacuum chamber, which is the atmospheric pressure of the liquid crystal cell 1, is reduced, the air inside the liquid crystal cell 1 is discharged through the injection hole 1a of the liquid crystal cell 1, and this liquid crystal cell 1 is shown by the imaginary line in the figure. When the pressure in the vacuum chamber is increased to atmospheric pressure after being immersed in the liquid crystal 3, the liquid crystal 3 in the liquid crystal container 2 is injected into the liquid crystal cell 1. FIG. 11 shows a case where an injection hole 4a is formed at a corner and liquid crystal 3 is injected into the liquid crystal cell 4. In this case, the liquid crystal cell 4 is immersed in the liquid crystal 3 in the vicinity of the injection hole 4a.

Also, JP-A-61-275726, JP-A-60-
41017 and Japanese Unexamined Patent Publication No. 57-24914 disclose methods for injecting liquid crystal into a liquid crystal cell using a liquid crystal suction member containing liquid crystal. By pressing the liquid crystal against the injection port and injecting the liquid crystal, the amount of unnecessary liquid crystal adhering to the liquid crystal cell is reduced, and the number of steps for cleaning is reduced.

Furthermore, Japanese Patent Application Laid-Open No. 57-24915 and Utility Model Application No. 57-24915
Japanese Patent No. 8-103021 describes a method in which a capillary tube is used as a liquid crystal introduction tube, and these devices also reduce waste of liquid crystal and improve productivity.

(Problem to be Solved by the Invention) However, in the conventional method that adopts the immersion injection method, the liquid crystal cell 1 or the liquid crystal cell 4 is directly immersed in the liquid crystal 3 housed in the liquid crystal container 2, so that the liquid crystal 3 is Not only is it wasted as the liquid crystal adheres widely to the liquid crystal cell 1 or the liquid crystal cell 4, but also the number of steps required to clean the liquid crystal cells 1 and 4 to which the liquid crystal 3 has adhered increases, which increases the manufacturing cost.

In addition, with conventional methods that use capillary tubes, liquid crystal suction members, etc., it is necessary to position the liquid crystal capillary tubes, liquid crystal suction members, etc. facing the injection port, making it difficult to inject liquid crystal into many liquid crystal cells at the same time. is difficult and requires improvement to increase productivity and reduce manufacturing costs. Specifically, when an injection hole is formed in a liquid crystal cell that opens not in an end face part but in a flat part, for example, an injection hole 5a is formed in a liquid crystal cell 5 shown in FIG.
When trying to inject liquid crystal through the capillary tube, it is not possible to press a liquid crystal suction member or the like against the injection hole 5a opened in the flat surface, and even if a capillary tube is used, the above-mentioned difficulty becomes extremely significant.

As described above, with the conventional method and apparatus for injecting liquid crystal into a liquid crystal cell, it has not been possible to improve productivity and reduce manufacturing costs.

(Purpose of Initiation) Therefore, the present invention reduces the adhesion of liquid crystal to liquid crystal cells, makes it possible to simultaneously and easily inject liquid crystal into a large number of liquid crystal cells, and improves the productivity of liquid crystal display elements.
The purpose is to reduce manufacturing costs.

(Structure of the Invention) In order to achieve the above objects, the method and device for injecting liquid crystal into a liquid crystal cell according to the present invention have the following features: (1) the atmosphere around the liquid crystal cell is reduced from atmospheric pressure to a predetermined pressure, and the The process includes discharging the air inside the cell through the injection hole, and inserting the liquid crystal cell near the injection hole into the upper part of the slit formed in the cell insertion tool in an atmosphere of a predetermined pressure, while inserting the cell insertion tool into the upper part of the slit formed in the cell insertion tool. The injection hole is immersed in the liquid crystal, which is sucked up by capillary action inside the slit, and the atmosphere around the liquid crystal cell is returned from a predetermined pressure to atmospheric pressure. and (2) an apparatus for injecting liquid crystal into a liquid crystal cell through an injection hole formed in the liquid crystal cell, the apparatus comprising: a step of injecting liquid crystal into the liquid crystal cell through an injection hole formed in the liquid crystal cell; A cell inserter having an insertable slit formed in the upper part, a liquid crystal container capable of storing a liquid crystal therein and allowing the cell inserter to be immersed in the liquid crystal so that the liquid crystal immerses the lower part of the slit, and a pressure reducing means capable of reducing the pressure of the atmosphere from atmospheric pressure to a predetermined pressure and discharging the air inside the liquid crystal cell through the injection hole; This method is characterized in that the liquid crystal is sucked up and the injection hole of the liquid crystal cell is immersed in the liquid crystal at the upper part of the slit, from which the air inside is discharged by the pressure reduction means.

Embodiments of the present invention will be specifically described below based on the drawings.

1 to 6 are diagrams showing a first embodiment of an apparatus for injecting liquid crystal into a liquid crystal cell according to the present invention.

First, the configuration of this device will be explained. In FIGS. 1 to 3, reference numeral 11 denotes a liquid crystal cell constituting a twisted nematic type (hereinafter referred to as TN type) liquid crystal display element, and the liquid crystal cell l1 has, for example, a pair of electrode-equipped plastic film substrates 12A and 12B as electrodes. They are bonded together at the periphery with a sealant 13 with a predetermined gap in between so that the surfaces (not shown) face each other, and the thickness is 0.21 mm. Further, the liquid crystal cell 11 has an injection hole 11a formed in the plastic film substrate 12B, and the liquid crystal L put in and housed in the liquid crystal container 14 is injected into the inside through the injection hole 11a.

Reference numeral 15 denotes a cell insertion tool made of, for example, a corrosion-resistant aluminum alloy, and a plurality of slits 16 are formed at a predetermined pitch in the cell insertion tool 15, extending perpendicularly to the longitudinal direction and having a groove width W larger than the thickness of the liquid crystal cell 11. This cell insertion tool 15 is fixed to the liquid crystal container 14 so that the liquid crystal L soaks the lower part of the slit 6, and the liquid crystal L immersing the lower part of each slit 16 is raised to a height corresponding to the groove width W of the slit 6 due to capillary action. Only Sa H can be sucked up. The relationship between the groove width W and the height H was measured using a ZLI system for TN type liquid crystal display elements manufactured by Merck Co., Ltd. as the liquid crystal L, and the values were as shown in the table below.

Further, as shown in FIG. 4, a plurality of liquid crystal cells 11 are arranged and held by cell holders 17 at equal intervals to the pitch between the slits 16, and the cell holders 17 are used to hold each liquid crystal cell 11.
Note: The vicinity of the bid 11a is positioned so as to face the slit 6 of the cell insertion tool 15, and is connected to the liquid crystal container 14 by bolts or the like (not shown).

Specifically, the cell holder l7 includes cell guides 18L and 18R that guide the liquid crystal cell l1 on both left and right sides so that the liquid crystal cell l1 can be inserted into the slit 16 with a predetermined gap maintained by l18a;
A pair of frames 19 (only one is shown) connecting the cell guides 18L and 18R at both ends; a cell presser bar 22 rotatably supported by the frame 19 at both ends via a pair of brackets 21; It consists of a stopper 23, etc., which is fitted into a guide #19a formed on the frame l9 at both ends and is movable along the groove 19a, and is guided by the cell guides 18L and 18R to stop the stopper 23.
A plurality of liquid crystal cells 1l supported by the liquid crystal cells 1l can be simultaneously inserted into the slit l6 by moving the stopper 23. Then, the slit 16 of this liquid crystal cell l1
In order to facilitate insertion into the cell inserter 15, a chamfer C is provided at the entrance of the slit 16 (see FIG. 3).

On the other hand, the liquid crystal cell 11, the liquid crystal container 14, the cell insertion tool 15, and the cell holder 17 are placed in a vacuum chamber (pressure reducing means) of a vacuum device (not shown), and this vacuum device uses air in the vacuum chamber, that is, The atmosphere around the liquid crystal cell l1 is reduced from atmospheric pressure to a predetermined pressure, and the air inside the liquid crystal cell 11 can be discharged to the outside through the injection hole 11a. The predetermined pressure here is a pressure value close to vacuum within a range in which the composition of the liquid crystal L does not change. Also,
The vacuum device can return (increase) the atmosphere of the liquid crystal cell 11 from the predetermined pressure to atmospheric pressure by introducing nitrogen gas or the like into a vacuum chamber that has been reduced to a predetermined pressure.

Note that the groove width W of the slit l6 in this embodiment is 0.3 mm to 1.5 mm with respect to the thickness of the liquid crystal cell 1l of 0.21 mm.
Although it can be carried out within the range of On++a, it is easy to manufacture the cell holder 17 mentioned above, and the liquid crystal cell l1 and the slit 16
Considering the accuracy of the gap, etc., the groove width W is preferably about 0.6 mm. In addition, the slit 1 in FIG. 3(a)
The horizontal width X of 6 may be set so that the liquid crystal L sucked up by capillary action in the slit 16 completely immerses the injection hole 11a.If the injection hole 11a is a round hole with a diameter of 11, the horizontal width 211111 or higher, but in order to facilitate positioning in the left and right width X direction and reliably prevent air bubbles from entering, 6L! It is preferably about li. Furthermore, the liquid crystal cell 11 has an injection hole 11a opening on the cell surface,
The liquid crystal cells 26 and 27 shown in FIGS. 6(a) and 6(b) may also be used.

Next, an embodiment of the method of the present invention using the apparatus of the first embodiment described above will be described.

First, a plurality of liquid crystal cells 11 are sequentially attached to the cell holder 17 with the bar 23 positioned at position S in FIG.
The liquid crystal cell 11 is held down by the cell holding bar 22. That is, a plurality of liquid crystal cells 1l are set in the cell holder l7. On the other hand, a predetermined amount of liquid crystal L is put into the liquid crystal container l4 so that the lower part of the slit 16 is immersed in the liquid crystal L.

``Skin stain'' L: Then, the pressure inside the vacuum chamber is reduced by the vacuum device from time T0 to T shown in FIG. 5 to change the atmosphere around the liquid crystal cell 11 from atmospheric pressure P0 to a predetermined pressure P. Depressurize, time T,
This is held for a period from 1 to T2, and the air inside the liquid crystal cell 11 is discharged to the outside through the injection hole 11a (deaeration).

On the other hand, after degassing the liquid crystal cell 11, preferably a little before time T2, the striker 23 is moved to the position S in FIG. By performing a moving operation, a plurality of liquid crystal cells 11 are simultaneously lowered and inserted into the upper part of each slit 16. At this time, the injection hole 11a is immersed in the liquid crystal L because the liquid crystal L that has immersed the lower part of the slit 16 is drawn up to the upper part by capillary action. ``Going in and out 2'' Drunk L: Next, time T! to T3, the vacuum device changes the atmosphere around the liquid crystal cell 11 from a predetermined pressure P to atmospheric pressure P0.
The liquid crystal cell 11 is returned to the liquid crystal cell 11 through the injection hole 11a immersed in the liquid crystal L due to the pressure difference between the internal pressure and the external pressure of the liquid crystal cell 11.
Inject liquid crystal L into. Then, the atmospheric pressure P0 is maintained until the liquid crystal L is completely injected (filled) into the liquid crystal cell 11, that is, from time T to T4.

Sealing second washing process Next, the stopper 23 is returned to position S1, a plurality of liquid crystal cells 11 are simultaneously pulled out from the slit 6, and the cell holder 17 is separated from the liquid crystal container 14 or the liquid crystal cells 11 are taken out from the cell holder 17. After cooling, the injection hole 11a is sealed with a sealant. Next, the liquid crystal L adhering to the liquid crystal cell 11 is removed by cleaning or the like, but since the liquid crystal L is a very small amount adhering only to the vicinity of the injection hole 11a corresponding to the horizontal width X of the slit 6, , simply clean only the vicinity of the injection hole 11a. If only the vicinity of the injection hole 11a of the liquid crystal cell l1 is immersed in the liquid crystal L sucked up by the slit 16 in this way, even if the injection hole 11a opens on the cell surface, many liquid crystal cells The liquid crystal L can be easily injected into the liquid crystal container 11, and only a small amount of liquid crystal L can be injected into the liquid crystal container 14 during one injection. Furthermore, waste of the liquid crystal L can be reduced and the liquid crystal L can be removed by simple cleaning. Therefore, the pitch of the slits 6 and the liquid crystal cell 11 due to the cell holder 17 are
Not only is it possible to simultaneously and easily inject liquid crystal L into a large number of liquid crystal cells 11 with a simple configuration that matches the pitch of the arrays, but it is also compatible with various types of liquid crystal cells with different shapes, greatly increasing productivity. improve. Furthermore, a plurality of liquid crystal cells 11 attached to the cell holder 17 can be easily handled at the same time.

7 and 8 are diagrams showing a second embodiment of an apparatus for injecting liquid crystal into a liquid crystal cell according to the present invention.

In FIGS. 7 and 8, 31 is an injection hole 3 that opens on the cell surface.
1a, and the liquid crystal cell 3l is, for example, a pair of glass substrates 32A and 32B with electrodes bonded together in substantially the same manner as the liquid crystal cell 11 of the first embodiment, and has a thickness of 1.0 mm. be. Reference numeral 33 denotes a cell insertion tool in which a plurality of slits 34 having a groove width of 1.6 mm are formed, and the cell insertion tool 33 is fixed in a liquid crystal container 35 that accommodates the liquid crystal L. The liquid crystal container 35 is supported by support means (not shown) so as to be rotatable within a predetermined angle range (for example, 90 degrees) together with a cell holder (not shown) that is substantially similar to the cell holder 17 in the first embodiment. By operating the support means, the liquid crystal cell 31, cell inserter 33, and liquid crystal container 35 can be integrally rotated back and forth between the state shown in FIG. 7(a) and the state shown in FIG. 7(b). can. That is, the liquid crystal container 35 can be rotated by a predetermined angle while containing the liquid crystal L. In the state shown in FIG. 7(a), the slit 34 located above the liquid surface H1 of the liquid crystal L is shown in FIG. 7(b).
The cell holder is lowered to the state shown in FIG. The injection hole 31a is immersed in the liquid crystal L. Note that the liquid crystal cell 31, cell inserter 33, liquid crystal container 35, cell holder, support means, etc. are placed in the same vacuum chamber as in the first embodiment.

To explain one embodiment of the method of the present invention using the device of the second embodiment, first, a plurality of liquid crystal cells 31 are set in the cell holder, while a predetermined amount of liquid crystal L is put into the liquid crystal container 35. . At this time, the liquid crystal cell 31 and the like are in the state shown in FIG. 7(a). Next, the atmosphere around the liquid crystal cell 31 is depressurized and maintained in a vacuum chamber in the same manner as in the first embodiment, and the air inside the liquid crystal cell 31 is discharged through the injection hole 31a, while the supporting means is operated. and remove the liquid crystal cell 31, cell inserter 33, liquid crystal container 35, and cell holder as shown in FIG.
Rotate integrally to state b). At this time, the lower part of the slit 34 is the liquid level H of the liquid crystal L in the liquid crystal container 35! The liquid crystal L is immersed further into the liquid crystal L, and as a result, the liquid crystal L is sucked up slightly above the liquid surface H8 within the slit 34. Next, the injection hole 31 of the liquid crystal cell 31 is opened using the cell holder.
The vicinity of a is inserted into the slit 34 to a predetermined depth. At this time, the liquid crystal L is sucked up by capillary action into the narrow gap above the slit 34 into which the liquid crystal cell 3l is inserted, and the injection hole 31a is immersed in the liquid crystal L. Next, the liquid crystal cell 31
The surrounding atmosphere is returned to atmospheric pressure, and the liquid crystal L is injected into the liquid crystal cell 3l through the injection hole 31a immersed in the liquid crystal L due to the differential pressure between the inside and outside of the liquid crystal cell 31.

Even if the liquid crystal cell 31, the cell inserter 33, the liquid crystal container 35, etc. are rotated together in this manner and the vicinity of the injection hole 31a is immersed in the liquid crystal L, it is possible to easily inject the liquid crystal L into a plurality of liquid crystal cells 31 at the same time. The same effect as in the first embodiment can be obtained.

FIG. 9 is a diagram showing a third embodiment of an apparatus for injecting liquid crystal into a liquid crystal cell according to the present invention. In FIG. 9, 41 is a liquid crystal cell having an injection hole 41a, and 42 is a plurality of slits 43 into which the liquid crystal cell 41 can be inserted.
The cell inserter 44 is a liquid crystal container having a liquid crystal storage portion 44a on one side in the longitudinal direction of the cell inserter 42, and the cell inserter 42 is fixed to the liquid crystal container 44. Further, the liquid crystal container 44 can be rotated together with a cell holder (not shown) around a rotation axis perpendicular to the longitudinal direction of the cell insertion tool 42, and the liquid crystal inside the liquid crystal container 44 can be rotated by rotating the liquid crystal container 44. The lower part of the slit 43 can be immersed in the liquid crystal L from the liquid level H4 by moving the liquid crystal L to the liquid level H or H4.

To explain one embodiment of the method of the present invention using the device of the third embodiment, first, a predetermined amount of liquid crystal L is added to the liquid crystal container 44.
After setting the cell insertion tool 42 in the vertical direction so that the liquid level of the liquid crystal L becomes the liquid level H (the state shown in FIG. 9), remove the liquid crystal cell 41, the cell insertion tool 42, and the liquid crystal container. 4
The atmosphere around the liquid crystal cell 41 is reduced from atmospheric pressure to a predetermined pressure and held therein in a vacuum chamber containing the liquid crystal cells 4 and the like, and the air inside the liquid crystal cell 41 is degassed. When the inside of the liquid crystal cell 41 is degassed, the liquid crystal cell 41 is adjusted so that the liquid level of the liquid crystal L becomes the liquid level H4.
, rotate the cell insertion tool 42 and the liquid crystal container 44, etc., and then (also at the same time) insert the vicinity of the injection hole 41a of the plurality of liquid crystal cells 41 into each slit 43 at the same time using the cell holder to insert the liquid crystal into the lower part of the slit 43. Soak in L. At this time,
The injection hole 41a of the degassed liquid crystal cell 41 is immersed in the liquid crystal L sucked up to the upper part of the slit 43 by capillary action. Next, the atmosphere around the liquid crystal cell 4l is returned to atmospheric pressure, and the liquid crystal L is injected into the liquid crystal cell 41 due to the differential pressure between the inside and outside of the liquid crystal cell 41. Even in this case, the same effects as in the first and second embodiments can be obtained.

Note that in the devices of the first to third embodiments, the liquid crystal cell 1
1, 31, and 41 are lowered to the liquid surface side of the liquid crystal L using a cell holder 17 or the like and inserted into the slits 6, 34, and 43. The liquid crystal container and the cell inserter may be raised toward the cell inserter, or both may be moved up and down to cause relative displacement. Further, after the liquid crystal L is sucked up into the slits 16, 34, 43, the liquid crystal cells 11, 31, 41 are sucked up into the slits 16, 34, 43.
, 43, it is also possible to encourage the liquid crystal L to be sucked up by capillary action after this insertion work.
Furthermore, if the shape of the liquid crystal containers 14, 35, and 44 is such that the liquid surface is wide when the liquid crystal L is injected, and the bottom area is small at that time, the degassing of the liquid crystal L can be promoted well, and the liquid crystal This is preferable because the drop in the liquid level during injection is also small.

(Effects) According to the present invention, the atmosphere around the liquid crystal cell is depressurized and maintained to exhaust the air inside the liquid crystal cell, and in the atmosphere, air is sucked up from the liquid surface by capillary action within the slit of the cell insertion tool. Since only the liquid crystal near the injection hole of the liquid crystal cell is immersed in the liquid crystal, it is possible to minimize the amount of liquid crystal that adheres to the liquid crystal cell when liquid crystal is injected, and it is also possible to Liquid crystal can be easily injected into two liquid crystal cells at the same time. As a result, productivity of liquid crystal display elements can be significantly improved and manufacturing costs can be reduced.

[Brief explanation of drawings]

1 to 6 are diagrams showing a first embodiment of the device of the present invention, FIGS. 1(a) and (b) are configuration diagrams of the main parts thereof, and FIG. 2 is a plan sectional view of the main parts of the liquid crystal cell. , FIG. 3(a) is a side sectional view of the cell insertion tool and the liquid crystal container, and FIG. 3(b) is a side sectional view of the cell insertion tool and the liquid crystal container.
4(a) and 4(b) are configuration diagrams of a cell holder that holds the liquid crystal cell, and FIG. 5 is a cross-sectional view taken along line BB in FIG. A time chart for explaining one embodiment of the method, FIGS. 6(a) and 6(b) are plan sectional views of main parts showing other aspects of the liquid crystal cell, and FIG.
FIG. 8 is a diagram showing a second embodiment of the device of the present invention, and FIG.
Figures (a) and (b) are configuration diagrams of the main parts thereof, Fig. 8 is a perspective view of the main parts thereof, and Fig. 9 is a perspective view of the main parts showing a third embodiment of the apparatus of the present invention. 10 to 12 are diagrams showing conventional examples, and 10S11
Each figure is a schematic configuration diagram of an apparatus for carrying out a conventional immersion injection method, and FIG. 12 is a plan view of a liquid crystal cell for explaining the problems of another conventional example. 11, 31, 41...Liquid crystal cell, 11a-3
ia, 41a... Injection hole, 14, 35, 44.
...Liquid crystal container, 15, 33, 42...Cell insertion tool, l6, 34, 43...Slit, L
······liquid crystal. Figure 5 Time lock Figure 6

Claims (2)

[Claims] (1) A step in which the atmosphere around the liquid crystal cell is reduced from atmospheric pressure to a predetermined pressure and the air inside the liquid crystal cell is discharged through the injection hole; While inserting it into the top of the formed slit,
The cell insertion tool is immersed in the liquid crystal so that the lower part of the slit is immersed in the liquid crystal, and the injection hole is immersed in the liquid crystal that is sucked up by capillary action within the slit.The atmosphere around the liquid crystal cell is returned from a predetermined pressure to atmospheric pressure, and the liquid crystal A method for injecting liquid crystal into a liquid crystal cell, the method comprising: injecting liquid crystal into a liquid crystal cell through an injection hole immersed in water. (2) A device for injecting liquid crystal into a liquid crystal cell through an injection hole formed in the liquid crystal cell, comprising: a cell insertion tool having a slit formed in the upper part thereof into which the vicinity of the injection hole of the liquid crystal cell can be inserted; A liquid crystal container capable of containing a liquid crystal and into which a cell inserting tool can be immersed in the liquid crystal so that the liquid crystal immerses the lower part of the slit, and an atmosphere around the liquid crystal cell is depressurized from atmospheric pressure to a predetermined pressure to remove air inside the liquid crystal cell. and a depressurizing means capable of discharging through the injection hole, the liquid crystal cell is sucked up by capillary action within the slit of the cell insertion tool immersed in the liquid crystal container, and the air inside is discharged by the depressurizing means. A device for injecting liquid crystal into a liquid crystal cell, characterized in that the injection hole is immersed in the liquid crystal at the upper part of the slit.